Metallic packing.



Patnted Aug. 15. I899. T. w. MITCHELL.

METALLIC PACKING.

{No Model.)

. I h Q I. z m

UNITED STATES PATENT FFICE.

THOMAS W. MITCHELL, OF OMAHA, NEBRASKA.

METALLIC PACKING.

SPECIFICATION forming part of Letters Patent No. 631,088, dated August 15, 1899. Application filed Decemherl, 1898. Serial No. 697,985. (No model.)

drawings, forming a part of this specifica tion, and to the letters of reference marked thereon.

My present invention relates to packings such as are usually employed to make the joints between moving parts-such, for instance, as the pistonrod and" piston-head of an engine-steam, fluid, or gas tight; and the object of the invention is to provide a simple, easily-applied, and effective packing which will adapt itself readily to the irregularities in the piston-rod or moving part, such as are usually occasioned by wear, particularly in horizontal engines,although it will be understood that the packing is applicable to any desired form of rod or casing, and I do not wish to be limited to the particular application illustrated in connection with a piston-head or gland of a steam-engine.

Referring to the accompanying drawings, Figure 1 is a plan or elevation of a gland of an engine with the top removed and the rod shown in section. Fig. 2 is a section at right angles to Fig. 1, on a reduced scale. Fig. 3 is a perspective View illustrating two of the packing-rings and a section of the piston-rod passing therethrough, the rings being separated to illustrate their construction. Fig. 4 is a detail elevation of one of the packingrings, showing the sections separated; and Fig. 5 is a detail perspective view of one of the ring-sections. Figs. 6 and 7 are detail perspective views showing modified forms of the sectional rings.

Like letters of reference in the several figures indicate the same parts.

In the said drawings the letter A indicates a piston or similar rod adapted to slide longitudinally through a cylinder-head or abutment B, which cylinder-head or abutment carries a packing-gland B, having a cover 13 all of any ordinary or preferred construction and forming'no part of my present invention.

The packings for preventing the escape of steam, vfluid, or gas around the piston-rod in its travels back and forth through the gland are arranged within the gland and confined thereby, and in the preferred construction two separate rings are employed, which are duplicates of each other; but it will be understood that one ring or more than two rings may be employed without in any wise departing from the invention. Each ringin its preferred form is made, preferably, of Babbitt metal and in two sections or segments, each adapted to encircle one-half, more or less, of the piston-rod and both being confined within a retainer, as will be presently described.

The pressure within the gland is utilized to advance the sections of the packing-rings against the piston-rod, and, if desired, in addition flat springs may be employed for a like purpose, as is common in this art, and in order to prevent the ends of the sections from springing open when underpressure or when worn the ends of the sections are confined between straight bearing-surfaces on the in nor sidesof the retainers, which bearing-surfaces, however, are parallel and arranged on opposite sides of the piston-rod, thereby permitting said-sections to advance or retreat to accommodate themselves to the irregularities in the rod or to take up wear as the same occurs. With such construction in order to prevent the passage of steam through the ring between the sections the sections are madewith cooperating projections or bearing-surfaces lying in planes parallel with the direction of bodily movement of the sections. Thus in the advance and retreat of the sections toward and from each other no joints are opened and no steam or pressure can seat 0 on the opposite side and with an outer flat face 0 which is adapted to rest against a corresponding face or bearing-surface (l in the retainer D. The opposite end of each of the sections in this preferred form has a projection 0 adapted to fit within the recess or seat 0 in the cooperating section, and a seat 0 adapted for the reception of the wall 0 on the opposite section. As thus constructed, the two sections when brought together will fit tightly, and it will be particularly noted that all of the contacting surfaces will rub together when the sections are advanced toward or moved away from each other and are arranged in planes extending parallel with the surface 0 or parallel with the flat face of the rings themselves. Thus they are constantly in contact during the movements of the sections toward and from each other, and the joints are so broken by the walls 0 that no steam or pressure can pass through between the sections and so escape around the pistonrod.

\Vhere two or more rings are employed in the same gland, they are preferably arranged to break joint, as illustrated clearly in Fig. 3, and this relative position is maintained by means of keys and slots D D in the retainers D.

Obviously the idea of providing packingring segments or sections with parallel substantially straight bearing-surfaces on the exterior, with a retainer having corresponding bearing-surfaces for preventing expansion or distortion of the sections or segments, andin providing the meeting ends of said segments or sections with plain flat bearing-surfaces which move upon each other in lines parallel with the retaining-surfaces may be embodied in a number of forms, andin Fig. 6 I have shown a construction which corresponds to the construction shown in Figs. 1 to 5, save that the projection c and recess 0 are omitted. In this form, then, the sections 0 at one end are provided with a flat surface a, corresponding to the fiat surface 0 and on the inner side they are provided with a flat surface a, while at the opposite end a flat surface a is provided, all of said flat surfaces being arranged in parallel planes. The two sections as thus constructed when brought together will be reversed with relation to each other and will occupy the position illustrated in Fig. 6that is to say, the fiat surfaces 0 and 0 will contact with each other and form sliding bearings and thefiat surfaces 0 will rest against and take their hearing on the parallel surfaces 61 in the retainers D. If desired, also, the sections may each have a wall extending up for contact with the flat faces of the retainer, and such a construction I have illustrated in Fig. 7, wherein it will be seen that each of the sections is provided with a vertical wall E at one side and at the opposite end with a wall E, which overlaps the wall E when the two sections are brought together. The outer faces or edges of each of the walls E and E are made flat at E and adapted to take a bearing on the surface 61 of the retainers, and in addition the said sections are provided with surfaces e 6, arranged paralled with the surfaces E thereby forming a construction through which it is practically impossible for any pressure to pass when the sections are properly pressed together and held against the rod.

Any usual means may be employed to retain the packing-rings and their retainers, which areIpreferably, though not necessarily, independent of the gland up against the end of the gland, and I have illustrated a spring F for accomplishing this purpose, which spring F bears against a plate or Washer F, and the latter in turn seats against the innermost packing-ring.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patentof the United States of America, is-

1. In a metallic packing the combination with a retainer having oppositely-arrangcd parallel internal bearing-surfaces, of packing-ring sections movable bodily toward and from each other in a direction parallel with the bearing-surfaces in the retainer and having external surfaces working in contact with said internal bearing-surfaces in the retainer, the meeting ends of said packing-ring sections having cooperating overlapping projections provided with contacting bearing-surfaces lying in planes parallel with the direction of bodily movement of the sections and at right angles to the plane of the internal surfaces in the retainer and other contacting bearing-surfaces lying in planes parallel with said internal bearing-surfaces in the retainer; substantially as described.

2. In a metallic packing the combination with a retainer having internal oppositelyarranged parallel bearingsurfaces, of packing-ring sections having external bearing-surfaces cooperating with said internal bearingsurfaces in the retainer, the meeting ends of said sections being provided with projections c and recesses 0 having contacting faces lying in planes parallel with the direction of bodily movement of the sections; substantially as described.

3. In a metallic packing the combination with the retainer having the internal oppositely-arranged parallel bearing-surfaces, of the packing-ring sections mounted within said retainer and having oppositely-arranged parallel external bearing-surfaces codperating with the bearing-surfaces in the retainer, the meeting ends of the said sections being formed with walls a and recesses 0 the overlapping faces between said meeting ends lying in planes parallel with the direction of bodily movement of the sections; substantially as described.

4. In a metallic packing the combination sitely-arranged parallel internal bearing-surfaces, with means for retaining said rings surfaces lying in planes parallel with the inwith the bearing-surfaces out of. alinement ternal bearing-surfaces in the retaining- T0 with each other, of segmental packing-rings rings; substantially as described.

mounted within the retaining-rings and hava 5 ing external bearing-surfaces cotipei'ating THOMAS MITCHELL with the internal bearing-surfaces in said Witnesses: rings, the meeting ends of said segments be- J. AUG. DOYLE,

ing overlapped and provided with bearing- O.'H. MARLING. 

